During the rolling of metal sheets (e.g., iron and aluminum), contaminants, such as debris of the metal sheets (metal debris) adhered to the surface of the metal sheets, are adhered to the work rolls of the rolling machine or the backup rolls of the work rolls (hereinafter “mill roll”). The contaminants such as metal debris adhered to the mill roll may reduce the quality of the surface of the rolled metal sheets. To prevent this, the contaminants, such as metal debris, adhered to the mill roll must be removed. To remove the contaminants such as metal debris, a brush roll, for instance, is used.
The brush roll rotates at high speed with its brush bristles pressed against the surface of the mill roll to scour the surface of the mill roll. The brush bristles are produced, for example, by incorporating abrasive particles into filaments made of a thermoplastic resin, such as nylon 6, nylon 66, nylon 612, and nylon 12. Examples of typically incorporated abrasive particles include silicon carbide and aluminum oxide (e.g., see Patent Literature 1).